T4 Engine tin: thermal design Options

[914werke]

So seeing a product recently got me thinking about the result of its application & my own observations of how well (or not) the T4 handles air flow, Engine block cooling & resulting oil temperatures. (IMG:style_emoticons/default/smile.gif)

Its somewhat well known that ...in the 914.. the T4 suffers from less than optimal cooling from the front mounted impeller/fan particularly to the #3 Cylinder
& that it is vitally important to seal the tins multiple openings to contain as much laminar air flow front to back over the finned cylinders.
In a gross approach, the goal was to seal the engine compartment "intake" air on top from the eng. heated "cooling" air below the tins.
When a motor is new and all its components serviced & refreshed, the design does, or did, a pretty good job.
After years of use (neglect), elements (oil dirt mice ext) conspire to restrict that air flow.
As well as eng. heat causing hardening of rubber pieces that are intended to help contain that cooling air below.
Now almost 50 yrs on I see fewer & fewer "STOCK" engine configurations which you can guess usually means more heat to deal with.
Jake addressed the cooling air via his(?) DTM solution, but IMO its not very practical for stock or near stock motors (& expensive)

The go-to response to eliminate that heat is usually an additional or a remote oil cooler which comes with its own set of challenges. (IMG:style_emoticons/default/confused24.gif)
How about KISS (IMG:style_emoticons/default/biggrin.gif) Has anyone used any of the Fiberglass based stick-on reflective heat shielding products on the engine-sides of the tin?
Idea being rather than allow heat absorption to all the those steel pieces reflect it back to carried away by the cooling air?

BTW Im not a Porsche engineer...but I did stay in a Holiday Inn last night (IMG:style_emoticons/default/happy11.gif)

[914_teener]

Jake and others use an exothermic coating on the cylinders themselves while masking the fins. I've written a couple of threads on this coating.

Absolutely agree that the airflow is NOT laminar and the the principals are quite simple.

Now....it may actually help to plug all the holes. Racing headers and engines increased performance ( via scavanging) by insulating the headers to increase air flow. So kevlar tins may actually help scavange.

I would submit that the stock heat exchangers actually might aid in air scavaging across the cylinders (which are creating most of the heat) with the cooling air as it is directed downwards. The German engineers with the materials they had availble...what they were doing. If something worked better then...they would have done it.

External oil coolers also help although I never ran one and ran my car many many times in stock config in 120 Degrees plus ambient.

My two bits...and from experience.